Results of the large randomised phase II study (ACTS-GC) has announced at the 2007 Gastrointestinal Cancers Symposium in Orlando, USA, showed that the oral anticancer agent S-1 reduced significantly the relative risk of death in early stage gastric cancer patients by a significant 32 per cent as compared to curative surgery alone.

Based on the first interim efficacy analysis (N=1059) in June 2006, the study's data and safety monitoring committee (DSMC) recommended to the investigators that the study be stopped. The results (N= 1059) indicate that for all randomised patients overall survival at 3-years was 80.5 per cent for patients receiving S-1 and 70.1 per cent for patients undergoing surgery alone, with a hazard ratio (HR) of 0.68 (95%CI, 0.52-0.87, p=0.0024). The most common grade 3 or 4 adverse reactions for nausea, vomiting, diarrhoea, anorexia and haematological reactions were below or equal to 6 per cent.

The Steering Committee of the GI Symposium has granted a public health exception for the S-1 abstract. In the case of a public health exception, the research data should be made public as soon as possible so that physicians and patients may immediately begin to make treatment decisions based on the new information. This is applicable in the countries where the drug is approved.

S-1 is a novel oral fluorouracil anticancer product that combines 3 pharmacological agents: tegafur which is a pro-drug of 5 fluoro-uracil; gimeracil (5-chloro-2,4 dihydropyridine (CDHP))which inhibits dihydropyrimidine dehydrogenase (DPD) enzyme activity; and oteracil (potassium oxonate (Oxo)) a gastrointestinal side effects corrector.

Sanofi- aventis collaborates on the current clinical development and is leading the future clinical development and commercialisation of the product in the United States, Europe, and other countries in the world, except certain Asian countries.